Motor-control system.



E. R. CARICHOFF.

MOTOR CONTROL SYSTEM.

APPLICATION FILED IEB.19,1912.

1,037,433. Patented Sept. 3,1912.

Invention Eugene RCurichof'f.

Widnesses I His Atforney.

' STATES PATENT OFFICE;

"EUGENE R. camonorr, or scnnnmc mnr, new YORK, ASSIGNOB fro ELECTRIC comramr, A conronarion or NEW YORK,

moTon-con'rnoL SYSTEM.

Specification of Letters Patent.

Patented Sept. 3

To all whom it may concern Be it known that I, Etienne R. CARI- oHorr, a citizen of the UnitedStates, residing at Schenectady, in the county of Schenectady, State of New York, have "invented certain new and useful Improvements in MotorCont-roi Systems, ofwhieh the following is a sperificatiorn This invention relates to the control of electric motors and has for its abject the. provision of means whereby a plurality of motors will be started and brought to runnot ching 'rel ning specd in a reliable, simpleand ellicient manner. V V

My invention relates more specifically to the control of electric motors on What is known as the series parallel system. "With this system of control a plurality of motors are connected in series with each other and with a starting resistance, after which the resistance is gradually cut out and the motor is connected in parallel with part of the resistance in series with each motor. This resistance is then cut out and'the motors are connected in full parallel, These steps have in the past been accomplished generally by a controller which is operated inany desired manner, having contacts mechanically fixed with reference-toeach otherso as to cause the necessary connections to be made when the controller is". rotated. These connections have also been. made by the use of a plurality of contractors whicharearranged to operate successively to cause the necessary steps to be taken to bring about this result. These steps are commonly performed under the control of.

a master controller in the hands .of the oper ator, this master cont-roller controlling the c rcults of the various cont-actors,

In my previous application, Serial No.

504,321, I have disclosed means for causing a time interval between the-closing of the contactors. This arrangement broadly stat-ed, covers what known a'two Wire finder "the control of a't 'such 'a's a assume to "cause the tweeters-rd be actuated successirely trith "predeten' minedbetween operation "of the plied this two wirenotching relay resistance 'contactors have dropped parallel 'mntactors close to connect the m'o successive contactors. These relaysiareqlilree wise under the control of themastertcon i safe value. In my later application Seri al.;

No. 643,086 I have shown another -form two wire notching mechanismx const'tutingmo a combined time limit mechanism in; licln, the e'il'ect of the retapding mec hanis dashpot is varicrl by the currenh ;-I n.;ca rry.; ing out my present inventionf. 1,; haye ap.-.,

to M series parallel system arrangedin a way as to secure the maxirnurn fliciency-of, operation combined with: the. minimu: number of working parts. In this, amen... tion I have shown thetype of tWO Yi1'5%70 notching relay disclosed in my. .last" m ntioned application. It is obvious,,h'w' that my invention is .in sense. imifedltoifl this particular relay constructio fact limited to any particular v I causing the retardation fend. energgzln of the various contactors; I In previous systemsoi-seriesfpa llel trol of the 'contactor .typelorr theffi step; of the master controller a'numhei jof1'ql' iso contactors close to connectthe two motorsfinf. series with each other and in ser es; withfthe f starting resistance. ,Inthenext position of the master controller, "the circuits are made whereby certain of the contactors snag, matic-ally actuated under the-icontrolof relay mechanism so as to cause a del yq progression of the mnmc'tms-w successively I cut out the sections of the starting re aneel After the last contactoncloses-"to-cutjo. out the last section of resistance another contact-or closes to establish-a {Miser 1% or what is known as a bridgeconnect-ion. :T-he -r closing of this bn'd 'inga ontactorbmks 1 the holding circuit for all 'of theresistance' contactors and causes them 'opern -fAs soon the bridging contact-or liftS andthe their;

tors inparallel. There is, howver,no-.der*10( lay-='be-tweer1 the closing 'of the bridging cont-actor and the closing of the parallel contact-ors so as to insure the dropping out of the resistance contactors. \Vhen the parallel cont-actors areclosed, the actuating circuit of the first resistance contactor is closed-so that ordinarily there would be no delay between the closing of the parallel contactor and the cutting out of the first resistance step. In order to overcome this ditliculty it has been the custom in the past to use one additional contactor which-is the contactor short circuiting the last section of -.resistance simply for the purpose of cansing this delay. In carrying out my present invention I eliminate this extra contactor which cuts out the last section of resistance and causes the necessary delay between the establishing of parallel connections and the cutting out of the first resistancestep by a novel arrangement in which the necessary delay is produced'by a time limit relay and r the extra contactor is eliminated. By my arrangement a delay is likewise caused between the establishing of the bridge contactor andthe establishing of the parallel connections so as to insure the resistance oontactors time to drop out.

Other objects and purposes of my invention will appear in the course of the following specification in which I have shown my invention embodied in concrete form for purposes of illustration.

In the accompanying drawing Figure 1 is a diagram showing the circuit connections of my complete system; Fig. 2 is a simplified diagram showing only the motor circuit connections to be read in connection with the key shown in Fig. 3 and Fig. 3 is a key of the variouscircuit connections.

In order to simplify the description of this systemv and to make it more easily readable I have shown the motor circuits in Fig.

- ply combinations of contactors which successively occur. It will be seen by reference to Fig. 2 that the closing of the contactors 1, 2 and 7 causes the motors M and Mto be connected in series with the respective fields F and F and in series with the resistance sections R, R, R R and R The overload relay 0 is likewise connected in this circuit. The next step, it will be seen from the key, causes the contactor 3 to close which short circuits the resistance section R On the third step contactor 8 closes, thereby short circuiting the resistance R. Onthe fourth step the contactor 4 closes thereby short circuiting resistance R. On the fifth step the contactor 9 closes thereby short circuiting the resistance R. In this position the resistances are therefore all short circuited with the exception of R On the sixth step contactor 5 closes, which short circuits all the resistance including resistance R This also de'energizes all the other resistance contactors and allows them to' drop out. In this position the motors will be in full series. On the seventh step the two contactors 6 and 10 are closed, thereby connecting the two motors in parallel. As soon as cont-actors 6 and 10 close the contactor 5 is opened there by leaving corltactors- 1, 2, 6 and 10 closed. With these contactors closed the motor M is connected across the line in series with resistance R R and the motor M connected across the line in series with resistances R and R. On the eighth step contactor 3 closes to short circuit resistance R. On the ninth step the contactor 8 closes to short circuit resistance R. On the tenth step con-- tactor 4 closes to short circuit resistance R and on the eleventh. step contactor 9 closes to short circuit resistance R. The two 1notors are now connected across the line in parallel with each other and with no resistance in circuit, that is, the motors are in the normal running condition.

The above is a description of the various arrangements of the motor circuits and it will therefore be unnecessary to describe these motor circuits in connection with Fig. 1. -The description of Fig. 1 will be confined to the arrangements whereby the various contactors are controlled. In Fig. 1 the contactors are numbered to correspond with the numbering in Figs. 2 and 3. The master cont-roller E has four positions A, .B, C and D through which the trolley T is connected to various contactors. The relay mechanism 0 is of the type disclosed in my application Serial No. 643,086. Thismechanismconsists of two relay windings 11 and 12 each provided with cores or plungers 13, l-ft, respectively, having at their lower end contacts 15 and 16. Each plunger is retarded in its downward movement by a dashpot l7 and is quickly moved upward by its COll. There is a common magnetic frame for the two relays consisting of the parallel bars 18 and 18 through which pass the two adjustable cores 19 and 9.0 of the overload coil .7.

The cores l4 ahd 13 are movable through the lower bar 18 so as to make contact in arrangement. is such that. \Vl'l811;0l1, coil -say, ""t'oninstance, coil 12, is energizedrits cor ll rise uickly and opens the circuit'ot the ooil l'l at the cotitactlt. The return move-5 5 .nentot this contact. is under thecontrol the flash-pot and of thecurrent coil roj 1 Upon thedenergizationofthe coil 12 the core Ll will start to drop retarded by the dashpot and also-retarded by the flux generated by the current intheseries coil 0, the retarda- -.tion de peuding,therefore upon the current. hen t he 'curre1 it--falls below a predeter; mined safe Yaltie the core will drop and energize the coilqll In like manner, when 15 the Ql'Q'tQfiaQDil: 11 is pulled up it subsequently ,(lrops ender the timeand current. retardation. 1 Kaol n-clay as it li"t rcoinpletes the circuitaof one or more contactors so that the contactors will heenergized .-;i\c.

cessirelyl,witl anthne interval depending upon the current between the successive enei'gizatio11n.-'-@;- t

Referring noiwoto Fig. 1, it will he seen tlmtgfw-he-nuthe master controller E is moved t0:fillg:filfil i[)(l5ltlOll5.;WlllCll is shown as posi- .;-ti0nia -;:olu'rent,-:passes from. the trolley T titre-ugh:the-windings of contact-01's l and 2 togrouml:Gmugwhen contactor 1 closes it energizes the winding of contactor 7 so that $0 ii-trfliexypttiitiorr;kzcontactors 1, 2 and T are .;-closed. wlrliisiritm-iill be seen from Fig. 2, connects-the,motors and resistances in series. hen the-controller moved to position B wire 21 is energizetha circuit passing through the-trolleylithrough wire 21, through the wintei'loo'leing contacts on the contactor T, thrhughthecoil L2. of the relay 0. through contacts/15oom 'thei:core ot-eoil l1. thence tl'lR-QilghilitiGIlOGk 23' on contactor 5 through flock;Q hontontactor 3. through the cue sizing winding of contactor 1:3. and thenee'togrmlnd through the upper interloc ks-onlcontactorsvtt. t and 9. This causes tIieII-ORtacUm-B tort-lose thereby euttirr; out

section of-res'istancel-t. The closing cf the contuctor 3niestablishes a holding c 'enit througi-rthe 'interhick 25 and break. its energining circuit at the interlock '24. The breaking of the energizing circuit. causes t .ie winding 121 tir'hetleiinergized thereby allcn ing'it' s' core l la td-(lrop under the control of the-current and the dashpot. currents ifal ls to a proper value due to 'the. spedingrup oftthe motors, the core ll will (-om'pklet :a acimnit through the coil: {1 1.. The tenrgivzin'ig:ournennnrill now pass-front zthe' wire21 tderoughxt'liecoil=11' a ml contac 5 Alifiyi thence tthrmiglrt to the interlock dl'fon? contaetqr i8; thenoe til roilgh athe; energizing; winding of cont-actor 8 a nd throughthe tin-Z terloek ofcont-"actor 3 a nd iback to grounth f Itwill-"he noted that the closing of contnctor 3 nvadett-'possib1efor-the contactor t -,to' close.""Th'ewtoeing :rof con-ttictorn '8 31mm hen the i ll lp ltt tl ,anergizeal,therebypermitting the plunger circuits '1 thesection ot? AESlsiltl'liCQ R". like manner when the contact closes it opens its own energizing 'circuit t the inter:

lock}? end comp-letesa holding circuit through interlock-29. t This causes the wind 12 to drop as before until it" finally completes the circuit at contact 15. In this way the two plungers 13 and 1-! cperate alternatel; under the control of the current in the motor circuit to complete the circuit of the successive contactors. It will be understood that each .contactor as it closes makes it possible for the succeeding contactor to beenergized. The next contactor to he closed is contactor 4 which short cilrfiiil's. va s ction of rc i-atant-e R and this is followed by the closing of contactor which short circuits section of resistance ll. Following the closing of contactor 9 contactor 5 clones which establishes full series.- The contactors s and 5 are therefore energized through the contacts on core 13 of the relay and contactors t? and 9 are ener: gized through the contacts on the core 1- The motors are now in full series position, the first six steps shown on Fig. 1-; having been taken. 'hen the master controlleris moved to the position C the wire 30 will he energized. The. energ Ling" current from wire 30 will therefore pass through the interlock 31 on cont-actor 5 to interlock 22 on contacttn' T, thence to wire 21 and the winding 11, contacts on the core 11. wire-32. interlcck winding of contactor t3. interlock 34, winding); of contactor L0, and back to ground. li'leclosiug of contactors G and 10 make the parallel connections of the motor, and the (loving of contactor 1Q det nergizes contactor 5 and causes it to open. It .will be seen that hetween the closing of the crutactor which caused the opening of the other resistance contactors. and the losing of'contactors L and 10. which made the parallel connections. there is an interval caused lay the delay in the relay 0. thcrtby insuring that the contactorsv willhe in their full open position before: the parallel con-' nections are made. Ccntactcrs 1. (land 10 are now closed and the motors are connected in parallel. Contactor 7 being ()l)tl 1=, resistance R is not in circuit. but resistances R and R are in series with the motor M while the resistances It and R are in series ith the:motoclllfi: When now the master. ittroller his fniozvedt to: position d) th e' wii-re A which j-isnleen ergrizerl tin tzhesposition: G is agadn energized 5 thus: causing tlre resistancet icontaclieitiltohgetuelosonn progression. wi s. ahottee;the;ffilistlicsmfadtor tooclosflmm Clttlh; 1,;-

toetmoihwhieh short' circttitwthe SQt'IiGEk'r-itfi 25 resistance B elm wrll be'noted tlmt'the-aei is also an Interval betweenwthe oloil t-giofithe parallel leonneetienssti and 10 and'thet lusing of the first resistance contactor 3. Furthermore, this delay is brought about without the additional contactor, as has been the practice heretofore. This is one of the im portant features of my arrangement.

Following the closing of contactor 3 contactors S and 9 and 4 will be closed successively until finally contactors 1, 2, 3, 4, 6, 8, 9 and 10 are closed. This places the two motors in parallel across the line with no resistance in circuit. It will be noted that by this arrangement I have eliminated a contactor which has heretofore been used for short circuiting the resistance R As above stated, this contactor-"was not neces sary heretofore in order to cut out the series resistance since the closing of contactor 5 brought about this result. The extra contactor was, however, necessary in order to cause a time interval between the closing of the parallel contactors and the cutting out of the first section of resistance. The extra contactor has heretofore been caused to close immediately upon the closing of the contactors (i and 10 and made a circuit for the contactor 8. This produces a slight time interval preceding the closing of the first resistance contactor. By my present ar rangelnent, however, by carrying the energizing circuit of contactors 0 and 10 through the relay mechanism I am able to produce the desired delay preceding the closing of the first resistance contactor without the additional contactor and likewise produce a delay between the closing of contactor and the closing of contactors (i and 10 so as to give the resistance contactors time to get it'nlly open.

"hile I have described my invention as embodied in concrete form, it should be understood that I do not limit my invention thereto except as it is limited by the scope of the claims annexed hereto.

\Vhat I claim as new and desire to secure by Letters Patent of the United States, is 1 1. In a series parallel system of'motor control, a pair of motors and sections of resistance therefor. a plurality of contactors, annaster controller arranged to energize certziin of said contactors to connect the motors and resistances in series, a relay mechanism for controlling the energization of certain of said contactors to produce a time interval between the successive energizations, and connections whereby said contactors successively close under the control of said mechanism in delayed. progression to first cut out the resistance in series position then after the proper interval to establish parallel connections and finally after another intervalto cause the resistance contactors to again operate to cut out the resistance in the parallel position.

In a series parallel system of motor control, a pair of motors and sections of resistance therefor, a plurality of contactors, a master controller arranged to energize certain of said contactors to connect the motors and resistances in series,a combined time and current limit relay mechanism for controlling the energization of certain of said contactors to produce a time interval between the successive energizations thereof, and connections whereby said contactors succssively close under the control of said mechanism in delayed progression to first cut out the resistance in series position and close the full series contactor, interlocking connections whereby the resistance contactors are opened when the full series 0011- tactor closes, and connections whereby parallel connections are established after the proper interval following the closing of the full series contactor and finally after the proper interval causing the resistance contactors to again operate to cut .out the re sistance in the parallel position.

3. In a series parallel system of motor control, a pair of motors and resistances therefor, a plurality of contactors, a master controller arranged to energize certain of said contactors in the first position to conneet the motors and resistances in series, a.

two wire notching relay energized by the master controller in the second position to progressively actuate and give a time interval between certain other of said contactors including a full series contactor to cut out said resistance and establish full series there being only one contactor for each section of resistance cut out, interlocking connections whereby the resistancecon, tactors open when .the full series contactor closes, and connections through the relay in the third position of the master controller whereby certain other contactors are closed to establish parallel connections of the motors through all but the last section of resistance and open the full series contactor and in the fourth position to again energize the resistance contactors progressively through the relay to cut out the resistance connected in parallel. r

4. In a series parallel system of motor control, a pair of motors and sections of resistance therefor, a number of contactors equal to twice the number of resistance sections, a master controller arranged to energize certain of said contactors in the first position to connect the motors and resistances in series, a relay mechanism energized by the master controller in the second position to progressively actuate and give a time interval between certain of said contactors including a full series contactor to cut out said resistance, interlocking connec-,

tions whereby the resistance contactors are opened when the full series contactor closes and connections through the relay in the In witness whereof, have hereunto set 10 third position of the master controller my hand this 16th day of February, 1912. whereby certain contactors are closed to establish parallel connections of the motor EUGENE R. CARICHOFF.

and open the series contactor and in the fourth position to again energize the re- Witnesses.

sistance contactors progressively through BENJAMIN B. HULL.

the relay to cut out the resistance connected -HELEN ORFORD.

in parallel. 

